模拟一个ornithocheiraean pterosaur的起飞时刻臂
Benjamin W Griffin1,2, Elizabeth Martin-Silverstone1, Rodrigo V Pêgas3
1Palaeobiology Group, School of Earth Sciences, University of Bristol, Bristol, United Kingdom.
PeerJ
|August 9, 2024
概括
龙可能通过使用四足发射起飞来达到比鸟类更大的尺寸. 与双脚起飞相比,这种方法提供了更大的杆,可能克服飞行尺寸限制.
科学领域:
- 古生物学的古生物学
- 生物力学 生物力学
- 进化生物学 进化生物学
背景情况:
- 现存鸟类的动力飞行受到起飞尺寸限制的限制.
- 已灭绝的龙比现代鸟类大得多.
- 之前的假设提出两足或四足发射为龙起飞.
研究的目的:
- 以计算方式建模龙的起飞机制.
- 为了比较假设双脚和四脚起飞运动的生物机械优势.
- 为了研究龙如何在飞行中克服尺寸限制.
主要方法:
- 创建了一个5米的翼展ornithocheiraean pterosaur的计算肌肉骨模型.
- 34个关键肌肉被重建,以估计起飞期间的动力臂.
- 双脚和四脚起飞的动力学序列是根据现存的飞行脊椎动物模拟的.
主要成果:
- 对于双脚起飞的后肢时刻臂没有发现显著的增加.
- 没有观察到前肢时刻臂在四足起飞时明显增加.
- 四足起飞使用具有最大总发射适用时刻臂的肌肉.
结论:
- 四足发射可能为龙提供了更大的起飞杆.
- 这种增强的杆可以解释龙是如何实现比鸟类更大的飞行尺寸的.
- 需要对龙的肌肉力量进行进一步的研究来证实这些发现.
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